Lopez Lake and Santa Margarita Mussel Inspection Program

Mandatory vessel inspection required prior to launching!

Please practice responsible boating by ensuring that your watercraft is CLEAN, DRAINED, DRY, and MUSSEL-FREE before launching.

Per the Quagga and Zebra Mussel Prevention Program Standards, all vessels that have been on an infested waterbody in the last 30 days will not be permitted to launch at Lakes Nacimiento or San Antonio. Vessels are verified through an invasive species database before launch.

For a current list of infested waterbodies please visit the California Department of Fish and Wildlife website.

What can you do to prepare your vessel and save time prior to inspection?

  • Inspect all exposed surfaces - small mussels feel like sandpaper to the touch
  • Wash the hull of each watercraft thoroughly
  • Remove all plant and animal material
  • Drain all water and dry all areas, including ballast tanks
  • Drain and dry the lower outboard unit
  • Clean and dry all live-wells
  • Empty and dry any buckets, toys, skis, boating equipment in contact with the water
  • Dispose of all bait in the trash
  • If you've been on mussel-infested waterbodies within the last 30 days you will not be permitted to launch.

These requirements remain in effect until further notice.
Thank you for your help in keeping our local lakes mussel free!

NOTICE: It is unlawful (CA Fish & Game Code Sections 2300- 2302 and SLO County Code Chapter 11.20.120) to possess, import, ship, or transport in the state, or place, plant, or cause to be placed or planted in any water within the state, zebra or quagga mussels.

For any mussel-related questions please contact the SLO County Mussel Prevention Hotline at (805) 788-6006 (after hours voicemail only) or (805) 781-5111 M-F 7:30 am - 4:00 pm or email us at [email protected].


Invasive Mussels